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The funeral of the 15-year old victim, Aiwa Matsuo, took place on Tuesday

The Japanese high school girl who was arrested on Sunday has reportedly confessed to killing and dismembering her classmate, say local media.

National news agency Kyodo quoted police sources as saying the girl had admitted she "wanted to kill someone" and dismember a body.

The murder has made headlines in Japan which has seen a number of killings of children by children.

A similar incident happened in the same city, Sasebo, 10 years ago.

In the most recent case, the body of Aiwa Matsuo, 15, was found in the suspect's home early on Sunday morning, after she failed to return home and her parents called the police, said the Asahi Shimbun newspaper.

Police sources told local media the 16-year-old suspect had returned to her home, where she had been living alone since April, with the victim on Saturday night.

The suspect, who cannot be named as she is a minor, had then struck the back of Matsuo's head with a tool and strangled her with a rope in her home.

Matsuo's body was found with her head and left hand severed. Her belly was cut open.

Police sources said they found a hammer and saw at the suspect's home.

'History of problems'

She also appeared to have posted a number of messages, which include photographs of a bloody hand, on an internet bulletin board.

Police are now investigating these messages which began to emerge around two hours after Matsuo was thought to have died.

The suspect's mother had died of cancer last year and her father had recently remarried, local media said. According to acquaintances, she was preparing to study abroad.

Kyodo quoted people who knew her as saying that she had a history of problems.